Apparatus for drying arrays of textile threads



Jan.'22, 1963 H. KABELITZ ETAL 3,

APPARATUS FOR DRYING ARRAYS OF TEXTILE THREADS Filed July 2, 1957 5 Sheets-Sheet 1 Jan. 22, 1963 H. KABELITZ ETAL 3,074,178

APPARATUS FOR DRYING ARRAYS OF TEXTILE THREADS Filed July 2, 1957 5 Sheets-Sheet 2 I FIG.3 45

Jan. 22, 1963 H. KABELITZ ETAL APPARATUS FOR DRYING ARRAYS OF TEXTILE THREADS Filed July 2, 1957 5 Sheets-Sheet 3 $3 Q 5 E Q Q E MMMA Q E Q in: \w mac m0;

iNNN TN vdE w 1963 H. KABELITZ ETAL 3,074,178

APPARATUS FOR DRYING ARRAYS OF TEXTILE THREADS Filed July 2, 1957 5 Sheets-Sheet 4 JLEfiii W @J! gw' jlm i in M 61 FIG.9 m6 {06 U. @ILU 1963 H. KABELITZ ETAL 3,074,178

APPARATUS FOR DRYING ARRAYS OF TEXTILE THREADS Filed July 2, 1957 5 Sheets-Sheet 5 W 13 1; M ULU/fi 6 C5 al-0% I I! [I FIG. l3

Our invention relates to drying apparatus for the processing of fibrous materials, particularly to dryers for warp and other arrays of textile threads.

It is known, for such purposes, to provide a drying apparatus with a channel through which the material to be dried is conveyed along -a planar area of travel while a gaseous drying medium is forced to flow through the same channel in parallel to the traveling direction of the material. In the known dryers, the drying channel is located approximately along the center axis of the dryer unit so that the gaseous drying medium impinges upon the upper side as well as upon the lower side of the array of material to be processed, the blowers or impellers for circulating the drying medium and the heaters or heat exchangers for the medium being mounted above and below the central drying channel.

An object of my invention is to greatly reduce the space heretofore required for such drying apparatus.

It is another object of my invention to devise a dryer system of modular or building-block type, to permit the assembly of a dryer plant from a number of similar dryer units, in any desired series or parallel grouping, to obtain equipment of any desired size or drying capacity, and without sacrificing the afore-mentioned reduction in over-all space requirements.

To achieve these objects, and in accordance with a feature of my invention, I provide the drying apparatus, employed for fibrous material, particularly for warp or other arrays of threads, with one or more enclosed dryer units whose gas-traversed drying channel is located outside of the center zone of the unit on and along at least two sides of the unit, whereas the impelling and heating means for the gaseous drying medium are housed within the inner space or central zone of the unit. As a result, the space requirements of the dryer unit are greatly reduced.

According to another feature of the invention, the individual dryer unit has two drying channels located on opposite longitudinal sides thereof so that one of the two channels is formed between the hollow body structure of the unit and an adjacent similar dryer unit. The drying channels are either traversed sequentially by the drying medium, or some of the medium is guided through one of the two channels while another portion of the medium flows through the other channel so that the two channels of the unit are parallel connected relative to the flow of gaseous drying medium.

According to another feature of the invention, the in dividual dryer unit described above is provide with two impellers or blowers for circulation of the drying medium. In one embodiment of this type the two impellers are connected in series within the same current of drying medium. According to an alternative aspect, however, the two impellers of the unit produce respectively separate circulatory flows of medium, so that each of the two dryer channels of the same unit is assigned to its own impeller device. This has the advantage that the drying media passing through the respective drying channels may differ from each other relative to their chemical and/or physical properties. Such differences in properties of the drying media, in certain cases of application, have rrates atent ice a favorable effect upon the textile material to be processed. Such different drying media may be employed for the drying of sheets or planar arrays of threads by a drying medium flowing parallel to the traveling direction of the material, as well as for the drying of other material such as webs and fabrics. This expedient can also be employed in conjunction with drying apparatus of other types. For example, one way of applying this method is to treat the material at the beginning of the drying period with a drying medium which has lower gravity but is more strongly hygroscopic than the drying medium employed during the final period of the drying process. For other material to be dried, it is sometimes preferable to use a drying medium of higher gravity at the beginning of the drying period as compared with a medium effective during the final period. The particular way and the sequence in which the respectively different drying media are distributed in the drying process stages is dependent upon the particular drying conditions to be sat-isfied for a given job.

According to a further feature of the invention, the

drying channels of the above-mentioned dryer units are provided with flow control means which permit selectively shutting ofi the flow of the drying medium in individual drying channels of a unit. For example, if the material is passed only through a single dryer unit having two drying channels, then the second channel, when not needed for drying a particular material, can be shut off by means of flaps or the like members. If each drying channel of the unit has its own impeller device for the drying medium, then the unit may also be provided with means for shutting off the appertaining impeller.

Drying apapratus constructed according to the present invention, have a very significant advantage, as compared with those heretofore known, in that a plurality of similar dryer units,, without change in their exterior or interior design, can be assembled to form a single drying apparatus. The dryer units according to the invention thus form elements of a modular or building-block system which permits the use of individual dryer units of similar type, design and size, in any required number and arrangement irrespective of the desired over-all size and working capacity of the drying apparatus. Only the number of the dryer units that compose the apparatus, rather than the individual design of the modular units, is dependent upon the desired over-all size of the equipment.

In plural-unit systems built up from dryer units according to the invention, the mutually adjacent drying channels of neighboring dryer units may form together a common drying channel. This drying channel can be composed either of two sequentially located channels of the respective units or of two co-extensive channels located one beside the other. All the dryer units joined together to form a single drying apparatus are preferably enclosed and combined within a common housing. The material to be processed is first passed through a channel. of one dryer unit, then, if necessary, around one corner of this unit, and thereafter through another drying channel of the same or of a neighboring drying unit.

My invention also includes the following method of or expedient for performing a textile drying operation, this method being particularly applicable with the aid of drying units described in the foregoing.

When drying impregnated textile material, particularly arrays of warp threads that are impregnated with sizing agent in wet condition and are then to be dried by a gaseous drying agent, one of the available methods is to pass the gaseous drying medium parallel to the textile material at great velocity relative to the traveling speed of the material. The gas velocity may exceed the critical velocity. One of the dilficulties encountered with this drying method is that the impregnated, and still wet material, tends to hang downward and to touch structural parts within the interior of the drying chamber, ifthe spacing between the supporting members at the entrance and exit of the drying device is as large as is usually desirable in such installations. It is, of course, possible to provide an additional supporting member such as a guide roller within the channel of the drying device. However, since the impregnated sizing agent has not yet sufficiently hardened in the middle of the .drying channel, particularly when high through-put speeds are involved, such an intermediate supporting or guiding member for the material tends to detrimentally affect the uniformity of the impregnation. It is, therefore, another object of the invention to eliminate this deficiency.

For this purpose, and in accordance with another feature of the invention, only one side of the planar array of material is at first dried in one drying channel; and thereafter the other side of the material is dried preferably in another drying channel. With this method or expedient, it is of advantage to provide rollers or other guiding or direction-changing means for the material only at locations where these supporting means enter into engagement only with the pre-dried side of the web or array.

A particularly favorable way of drying textile materials in accordance with the method just described, is to pre-dry one side of the material in one drying channel, subsequently drying the same side within a channel formed by two neighboring drying units located side by side so that the other side of the material is simultaneously predried. Thereafter the material is passedinto a further drying channel, if necessary after again passing the ma terial over guiding or direction-changing rollers or other supporting means, with the result that the thickened side is subjected to subsequent drying. The drying medium, in-this method, may have any desired flow direction. However, it is in some cases preferable, at least in the first drying stage of each individual side of the material, to have the drying medium flow in opposition to the traveling direction of the textile material.

The foregoing and other objects, advantages and features of my invention will be apparent from the following description taken in conjunction with the drawings, in which a number of preferred embodiments of drying apparatus constructed according to the. invention are'illustrated by way of example.

FIG. 1 illustrates in vertical section a drying apparatus composed of two dryer units, each unit having one gas impeller and a heater.

FIG. 2 is a vertical end view partly in section of a warp-drying apparatus comprising two coactive dryer units. This view is taken on line II-II of FIG. 3.

FIG. 3 is a longitudinal section of the drying apparatus of FIG. 2, each dryer unit being provided with two impellers and two heaters.

FIG. 4 is a diagrammatic and sectional representation of drying apparatus which comprises four combined dryer units, each unit being similar to those shown in FIG. 2.

FIGS. 5 to 13 illustrate schematically nine dilferent modifications, each comprising an apparatus composed of four dryer units. These figures differ from each other in respect to the arrangement of the drying channel and the mode of passing the textile material through the channel, to satisfy or conform to respective variations in the drying method; and f FIG. 14 illustrates, schematically, an eight-unit apparatus, assembled from individual dryer units of triangular shape. 7 t

' The apparatus according to FIGS. 2 and 3 comprises two individual dryer units 1 and 2 which are mounted one slasher, that is, as an air slasher.

upper dryer unit 1 are two impeller devices or blowers 5, 6, and also the heat exchangers 7 and 8 which heat the gaseous drying medium. The lower dryer unit 2 is similarly equipped with impellers 10, 11 and heating devices 12 and 13.

The upper dryer unit 1 has a drying channel 14 extending longitudinally of the unit along one outer, or upper, side wall 32 thereof. A second drying channel 15 of unit 1 is formed longitudinally along the lower wall 31 of this unit. Analogously, the lower dryer unit 2 has two drying channels 16 and 17 extending along the longitudinal sides 'of the unit. Controllable pivoted closure flaps at the corners, such as those designated 18, 1?, 2t) and 21, permit the closing of individual drying channels, if not needed.

It will be recognized that the impeller-s 5 and 6 or 10 and 11, of each individual dryer unit, are connected in series relative to the flow of the drying medium, the

flow direction of the medium being indicated by arrows. For example, the drying medium issuing from the impeller 5 is first passed through the heater 7 and then passes by the flap 19 into the drying channel 15 and through that channel to volute chamber of the impeller 6. After issuing from the impeller 6, the same current of drying medium passes through the heater 8 and thence by the flap 18 and through the drying channel 14 back to the impeller 5. The circulation of the drying medium in the lower dryer unit 2 is similar to the one just described.

The material to be dried, for example an array of warp thread F just coming tom the size-containing bath, and still wet, is first passed through opening 36 into the uppermost drying channel 14. The warp material F is guided at or adjacent the entrance opening of the housing 3 by means of a guide roller 22. At the end of drying channel 14, the warp F passes over a guide roller 23 and passes along the front side of unit 1 to a directionchanging guide roller 24 through which the material passes between the upper dryer unit 1 and the lower dryer unit 2 to a guide roller 25, thus partitioning the intermediate space between the two units into the upper channel space 15 and the lower channel space 16. From guide roller 25, the material passes along the left side of unit 2 to a guide roller 26 whence it passes through the channel 17 before it leaves the housing 3 of the apparatus at the location of a guide roller 27.

It will be recognized that the drying medium is so guided in the respective channels that it flows in a direction opposed to the traveling direction of the material in each of the individual drying channels. Aside from pro viding for a'particularly good drying effect, this counterflow method has the advantage that the individual fibers,

for example of cotton, wool, natural hair and cellulose.

wool, are forced in opposition to the traveling direction of the thread, and thus are intimately placed or aligned against the thread. This result is pronounced when the gas is moved at very high velocities. This effect is augmented by the direction-changing guide rollers which also press protruding fibers against the thread. Consequently, after the material is dried, the thread surface is also smoothened. Thus the apparatus functions also as a This operation as a slasher is advantageous in the further fabricating of such threads, for example on weaving loomsr Two additional control flaps 34 and 35 are provided which permit the selective setting of the apparatus of FIG.

. 3 for series connection or parallel connection, in the sense of the travel of thedrying medium through the drying channels as well as with respect to the operation of the impeller devices. The two drying units are combined to form a single drying apparatus enclosed within the housing 3. The housing 3 is provided with removable'cover plates 37 and 38 at the rear and front walls respectively, in the regionwhere the textile material F passes between rollers 23 and2fi, and. between rollers 25 and 26. Removal of the cover sheets permits the observation of the processing condition of the material with the aid of measuring instruments, if desired. The lateral Chambers 39 and 40, adjacent cover plates 37 and 3 8, can be utilized to provide the abovementioned change in pressure, to promote vaporization resulting from the heat content of the textile material. For this purpose, the pressure in the lateral chambers is kept lower than the pressure in the drying channels. It is only necessary to connect the lateral chambers with the ambient air, through openings at 41 and 42 for example, or to provide for venting or positive circulation of ambient air by impeller means (not shown), in order to permit humidity to escape from the vaporization chamber.

According to another feature of the invention, the lateral, intermediate chambers 39 and 419 are provided with spreading devices to separate the individual threads of the warp material from each other. As shown for right chamber 39, spreader rods 43, or rollers, are mounted in the chamber. One thread passes on one side of the spreader member and each other, or alternate, thread passes on the other side. Approximately one half of all warp threads are diverted from the straight or direct path between the upper guide roller 23 and the lower guide roller 24. If desired, any other proportion of the threads may be thus diverted. The threads may also be passed over a third guide roller (not shown) between rollers 23 and 24. Provision of such third guide roller would cause displacement of the individual threads relative to each other, but such displacement can readily be compensated in the immediately following drying stage. This can be done by providing similar diverting means in the left chamber 40. In chamber 39 good separation of the parallel threads is readily secured because the impregnating material, such as sizing agent, has not yet hardened at this location. When the material leaves the drying apparatus at roller 27, all threads are again located alongside each other, as they were supplied into the drying apparatus, but the threads are now well separated from each other. Such separation of the individual threads from each other sometimes causes consider-able trouble, or is difiicult, particularly with fine wool or cotton yarns. Such difficulty is fully eliminated with the method and apparatus according to the present invention, which, as

described, insures good separation even with delicate thread materials. The compact design of the apparatus, aside from minimizing the over-all space requirements, also aifords the advantage that the heat losses to the environment are kept within small limits.

As stated above, the material F to be dried is first passed through opening 36 and over roller 22 into the drying channel 14 along the top side of the upper dryer unit. Thence, the material passes over guide roller 23 and through lateral chamber 39 to roller 24 and into the drying channels 15, 16. Thereafter, the material passes over rollers 25, 26 through lateral chamber 40 and into the drying channel along the bottom of the lower dryer unit, to leave the apparatus over roller 27. Simultaneously with this drying operation, the apparatus may be supplied with further material to be dried, for instance with a second array of threads F which enters at 42 and is withdrawn at 41 being passed only through the drying channels and 16, because a shorted drying period is suflicient for this material. It is further possible to move the second array of threads F at considerably lower speed than the traveling speed of F.

At each corner of the units 1 and 2, and adjacent to the flap valves, is a shaft 44 also serving as an intake or outlet pipe for introducing or removing gas or vapor treating agent. In this way local variations are obtained in the physical or chemical properties of the treating or drying agent or agents. As shown in FIG. 3, some of the conduits 44 carry a transversely extending deflector wedge 45, which can be pivoted by turning the conduit. De-

5 pending upon the operating conditions the wedges can be turned to prevent passage of the drying medium at the location of the arrow. The passage of drying medium at the opposite side of shaft 44 can be shut oif by means of the movable flap valves.

The apparatus according to FIG. 1 is likewise composed of individual dryer units in the manner of a buildingblock system. Each of the two dryer units 191 and 102 is provided with one or two impeller devices 1413 or 105, but is equipped with only a single heating device 107 or 109 for the drying medium. In the embodiment of FIGS. 2 and 3 the drying channels are virtually series connected relative to the flow of drying medium.

The flow conditions in the embodiment of FIG. 1 differ in that the drying channels are connected in parallel. Part of the drying medium, passing from the impeller 103 through opening 110 into casing 101 and through heater 107, flows through the drying channel 111, whereas another part of the medium leaving heater 107 passes through a drying channel 112. The material F, to be dried, is first passed through the drying channel 111, then through the combined drying channels 112 and 113, and ultimately through the drying channel 114. In this case, however, the flow direction of the drying medium is opposed to the travel direction of the material only in the drying channels 111 and 114, the material and drying medium have the same traveling direction in the two adjoining channels 112 and 113.

In FIG. 1 the thread or yarn F is supported on rollers 117 to 122, being drawn through the apparatus by any conventional winding spool. At the four corners of each unit 101 are transversely extending flap valves 123 to 126. Similar valves 127 to 130 are employed at the corners of lower unit 102. The two units are supported one above the other in housing 127. Shaft conduits 131, 133, for introducing or removing treating media, or for introducing atmospheric air are stationed at the corners, adjacent to the flap valves. The conduits 131 each pivot or carry pivoted deflector or closure wedges 132. The crkalnduits can also be employed to vent gas to the atmosp ere.

The blower 103 of FIG. 1 is located laterally off the drying unit, the air being blown through opening 11d into casing 1. It should be understood that each unit 1 or 2 may have two blowers, laterally located.

In both the embodiments, of FIGS. 1 and 3, each time the gaseous drying medium leaves a drying channel, it is first reactivated by being accelerated in the impeller or blower and thereafter heated in the heater, before the medium again enters into contact with the material in a drying channel. It will be observed, from inspection of FIGS. 2 and 3, that the reactivation zone is surrounded by the processing region or range for the textile material. The processing region comprises the channels in which the material to be processed or dried by the gaseous medium, which may be a current of dry air, is impinged by said medium. Each dryer unit further provides a storage or collecting space for the processing medium between the locations where the individual reactivation elfects take place. Such collecting space is provided, for instance, between the exit of the impeller and the entrance into the heating device. In this relation, it will be noted that in FIGS. 2 and 3, the gas passes from channel 14 through chamber 511, into impeller opening 5 and then through blower or impeller casing 28 (FIG. 2), from which it flows into compartment or collecting space 29 above heater 7. The gas leaving drying channel 15 enters the impeller casing and is passed from 6 to collecting space 30 below heater 8. Further medium-storing or collecting spaces are provided bztween the reactivation zone, on the one hand, and the entrance and exit openings thereto for the processing medium, on the other hand.

It is generally preferable to locate the reactivating devices, namely the impellers and heaters, and also the connecting conduits thereto, at least approximately in the uniformity in the heating of the drying medium, ordinarily difficult to avoid, is minimized within the heating device. The embodiment of FIG. 1, as compared'with that of FIGS. 2 and 3, affords the further advantage that the reactivating devices are located within a box structure whose walls close and separate the processing range from the reactivating zone. For example, a comparison of FIGS. 2 and 3 shows that a direct separation of the processing region from the reactivating zone is not fully achieved by the box-shaped design of the dryer unit in the embodiment of FIG. 3. It is necessary in FIG. 3 to provide additional channels or conduits to guide the drying medium, for example from the heating device 7 (FIG. 3) up to the place where the medium is blown onto the material, in the vicinity of the valve flap 19. This involves a repeated change in direction of the processing medium and thus entails power losses in the flow of that medium. In contrast, the guidance of the flowing medium in the embodiment of FIG. 2 is more straight-forward and involves only a minimum number of changes in flow'direction.

In th embodiment of FIG. 3, the hot processing medi- V um, after issuing from the heating device 7 or 8, first blows against the adjacent wall 31, or 32, respectively, of the drying unit, at locations approximately in the middle of each of the processing channels 14 and 15. At these locations, however, the processing medium then flowing within the channel 14, and 15, is already cooled down to a considerable extent, so that a high temperature gradient occurs Within the wall of structure 1 at this location. In addition, the wall portion 33 which separates the exit of the processing medium from the heater 7 from the entrance of the processing medium into the heater 8 also possesses a high temperature gradient. 7

These disadvantages, however, are eliminated in the embodiment according to FIG. 1 where the heated dry air enters into contact with the separating wall structure only shortly before it enters into one of the processing channels 111 to 114, so that the temperature gradient in this separating wall is relatively small. shaped design of the dryer unit according to the embodiment of FIG. 1, as compared with that of FIG. 3, is advantageous with respect to manufacture because, with the exception of the customary grille ahead of the heating devices 167 and 109, serving to ensure a smoothor quiescent flow of the medium, no partition walls are required for guiding the processing medium.

It has been found that the performance of the drying apparatus constructed according to the present invention can be further improved by providing a vaporization zone between each two successive drying channels, to serve the following purpose. During the drying of the material with the aid of the hot drying medium, the material develops or retains a considerable content of heat. Consequently, where an intermediate travel section between two individual drying steps is provided, an additional drying effect can be obtained by vaporization, if desired by simultaneously applying suction. This additional drying effect is particularly pronounced if the pressure in the intermediate section between the channels is lower than in the preceding, and/ or in the subsequent, drying channel.

A vaporization section between drying channels is pro- 7 vided in the intermediate space which must be traversed by the material when passing from one drying channel of a unit to another drying channel of the same unit, or of another unit in the same dryingapparatus. For example, the vaporization sections may be provided between the guide rollers 118 and 119 and also between rollers120, 121 of both units of FIG.,1. The change from higher pressure to lower pressure can be repeated during the travel of material through the drying apparatus. In some cases, it is advantageous to have the textile material'travel through the free atmosphere when passing through the Furthermore, the boxintermediate vaporization sections of the travel path so that the material has the opportunity of losing humidity to the ambient air. However, it is also possible to provide means for constrainedly establishing in the vaporization section other physical conditions than obtaining in the drying channels, such as a different atmospheric pressure, a di'lferent temperature, or a difierent hygroscopic behaviour of the medium acting upon the material.

As stated above, and according to another feature of the invention, the traveling textile material i made accessible within the vaporization sections of its travel, thus permitting the material to be inspected or approved from the outside of the apparatus in order to determine its particular condition at that location. 'For'this purpose, measuring devices for, testing the processing stage may be disposed at this location; and such measuring devices may be utilized for controlling or regulating the drying or other processing of the material, such as the degree of impregnation by sizing substance. Such regulation can be etfected manually as well as automatically, by varying the processing temperature, the How direction of the drying medium, or the traveling direction of the material to be processed. For some applications, it is desirable to permit the mixing of the drying media flowing through the individual drying channels with each other, and/or with the ambient atmosphere, in a controllable or adjustable mixing ratio.

FIGS. 4 to 14 indicate some or" the numerous possible combinations of dryer units, to form a single drying apparatus. It is apparent that the illustrated combinations far from exhaust all possibilities. FIGS. 4 to 14 are schematic, merely the impeller devices 103 to 1&6 and the heaters 107 to 110 being shown, in order to indicate the relative positions of the individual dryer units. The path of the material F to be dried as it travels through the individual units is also shown.

in FIG. 4, four dryer units, similar to those described above with reference to FIG. 1, are provided in housing 21. Two or" the units are located one above the other, me other two being positioned beside each other. The material F to be dried is first passed in the longitudinal direction through two sequential drying channels at 211 and 212. Only thereafter is the material F guided downwardly outside of and at the rear of the entire drying apparatus enclosed by the common housing 221. Thereafter, the material is passed between the dryer units at 33 and 214, and is then guided downwardly outside of and'at the front of the housing 21, at 215, to thereafter pass serially through the lowermost drying channel 216, 217 of the two lower units. The yarn F is supported by rollers 217 to 223 disposed in contact with one side thereof, and by centrally disposed guiding rollers 224 to 226 in contact with the opposite side. The heating devices are at 197 to 116.

FIG. 5 shows a processing path for the material F to be dried in a drying apparatus which is similar to that of PEG. 4, in respect to the unit employed, differing in arrangement in the following respects. The dryer units are reversed to permit travel of the thread through the apparatus from the right-hand side thereof. Moreover, only the two adjacent drying channels located between each two neighboring dryer units are utilized for drying the material. The four individual drying channels located on top of the upper dryer units and below the lower 7 units are not used, and may be shut off. The material F thus passes on a straight path horizontally through the apparatus.

FIG. 6 illustrates the use of the same units for drying two arrays of material F and F The latter are predried in the two outer upper and lower drying channels 311 and 33.2, respectively, and are then jointly subjected to further drying in the centrally located drying channel 313, between the upper and the lower units.

The various types of thread guidance and channel arrangement illustrated in FIGS. 7 to 13 are self-explanatory, in view of the foregoing. They exemplify the extreme versatility of a building-block system of dryer units constructed according to the invention.

It will be obvious to those skilled in the art, upon a study of this disclosure, that the invention is not limited to the embodiments particularly illustrated and described herein. For example, instead of constructing the individual dryer unit with a substantially rectangular cross section, units having other cross sections can be used in similar manner.

The apparatus of FIG. 14 comprises eight triangular housings 4th to 407 provided at each corner with controllable flap valves and with pivoted deflectors (not shown) similar to those of the units of FIGS. 2 and 3. The gas impeller intakes are shown at 413 to 429, and the heaters at 421 to 428. Any desired gas flow direction, and apportionment, is thus obtainable. The course of the yarn F over the various supporting rollers is selfevident. It is understood that the housing indicated at 429 may be designed either to provide intermediate yarn portions exposed to the atmosphere, or to reduced pressure in lateral compartments, as in FIGS. 2. and 3.

As is apparent from FIG. 14, the dryer units of generally triangular cross section alTord a grouping that provide a very long drying path within a minimum of overall space. The individual dryer units may have a triangular cross section representing triangles that are rightangled as illustrated in FIG. 14, or are equilateral, isosceles or scalene depending upon the particular requirements. In the dryer units of the type shown in FIG. 14, as well as those illustrated in the preceding figures, either two or three, or all sides, of the dryer units may be provided with drying channels which, if desired, may be individually equipped with shut-off means.

We claim:

1. A treating unit for assembly into an apparatus having at least two treating channels for treating textile thread material by a gaseous medium, said unit comprising a closed casing structure having opposite substantially planar walls, each of said opposite walls being adapted to form one side wall of one of said two treating channels of said apparatus, means located at opposite ends of each of said walls and forming respective gas inlets and gas outlets at opposite ends of each of said channels, said gas outlets being mutually formed at diagonally opposed corners of said casing structure, impeller means mounted on and depending from said casing structure for circulating said gaseous medium in a predetermined direction, said impeller means having an intake and an outlet opening, at least one of said impeller openings being located within said casing structure, said impeller means being located so as to draw suction from within said casing structure and to discharge back into said casing structure, duct means connecting said intake opening of said impeller means to respective ones of said gas outlets and connecting said outlet opening or" said impeller means to respective ones of said gas inlets, heater means within said duct means for heating said gaseous medium, and guide means associated with said casing structure for passing said textile material through said channels in spaced relation to the outside surfaces of said opposite walls and in a direction parallel to and countercurrent to said predetermined fiow direction of said gaseous medium through said channels, said casing structure and duct means forming together communicating passageways for cyclic circulation of the gaseous medium in a closed path by said impeller means and shaped so as to guide said medium through said heater means and through sm'd treating channels formed along the outside of said walls, and back to the impeller means.

2. A drying unit for assembly into an apparatus having at least two drying channels for drying textile thread material by a gaseous drying medium, said unit comprising a closed casing structure having opposite longitudinal, substantially planar walls, each of said opposite walls being adapted to form one longitudinal side wall of one of said two drying channels of said apparatus, means located at opposite ends of each of said walls and forming respective gas inlets and gas outlets at opposite ends of said channels, said gas outlets being formed at diagonally opposed corners of said casing structure, impeller means mounted on and depending from said casing for circulating said gaseous medium in a predetermined direction, said impeller means having an intake and an outlet opening, at least one of said impeller openings being located within said casing structure, said impeller means being located so as to draw suction from Within said casing structure and to discharge back into said casing structure, duct means connecting said intake opening of said impeller means to respective ones of said gas outlets and connecting said outlet opening of said impeller means to respective ones of said gas inlets, heater means within said duct means for heating said gaseous medium, and means associated with said casing structure for supporting and guiding said textile material through said channels in spaced relation to the outside surfaces of said one longitudinal side wall and in a direction parallel to and countercurrent to said predetermined flow direction of said gaseous medium through said channels, said casing structure and duct means forming together communicating passageways for cyclic circulation of the gaseous medium in a closed path by said impeller means, and shaped so as to guide said medium through said heater means and through said drying channels formed along the outside of said longitudinal walls, and back to the impeller means.

3. An apparatus for drying textile thread material with a gaseous medium, said apparatus comprising a housing, a plurality of substantially identical dryer units within said housing and disposed in spaced relation to each other, each of said units comprising a substantially closed casing structure having opposite generally longitudinally extending at least partially planar walls, said units being mutually positioned so that the longitudinally extending walls of adjacent ones of said units form together an intermediate drying channel for the material to be dried, impeller means and heater means within said casing structures of each of said units, said impeller means being located so as to draw suction from Within said casing structure and to discharge back into said casing structure, respective impeller means and heater means of re spective units being mutually interconnected and connected in communication with said intermediate drying channels for heating of said gaseous medium and for cyclic circulation thereof in a predetermined direction through said drying channels, impeller means and heater means, and means within said housing for guiding and passing the textile material through said intermediate drying channels in spaced relation to said longitudinally extending walls and in a direction parallel to and countercurrent to said predetermined direction of flow of said gaseous medium through said channels.

4. An apparatus for drying textile thread material with a gaseous medium, said apparatus comprising a housing, a plurality of substantially identical dryer units within said housing and disposed in spaced relation to each other and to at least one of the walls of said housing, each of said units comprising a substantially closed casing structure having opposite generally longitudinal at least partially planar walls, one of the longitudinal walls of one of said units forming together with an adjacent wall of another of said units an intermediate drying channel for material to be dried, the othere one or" said longitudinal walls of said one unit forming together with said one wall of said housing a respective outer drying channel for the material to be dried, impeller means and heater means at least partially within said casing structures of each of said units, said impeller means being located so as to draw suction from within said casing strucsame with said intermediate and outer drying channels for heating of said gaseous medium and for cyclic circulation thereof in a predetermined direction through said drying channels, impeller means and heater means, and means within said housing for gniiding and passing the textile material through said channels in spaced relation to said longitudinally extending walls and in a direction parallel to and countercurrent to said predetermined direction of flow of said gaseous medium through at least one of said channels.

5. An apparatus according to claim 4, said units being so mutually arranged Within said housing and relative to said means for guiding and passing the textile material through said channels that said drying material passes in a first stage through said outer drying channel and subsequently through said intermediate channels, said duct means of the impeller and heater means of the units which are in spaced relation to said one Wall of said housing being arranged to direct the drying medium only onto one side of the material in said outer drying channel, said duct means of the impeller and heater means of other ones of said units being arranged to direct the drying medium into said intermediate channels onto opposite sides of the material therein and in a common direction of flow on each side of the material in a respective intermediate channel.

6. An apparatus according to claim 5, said means for guiding and passing the material through said channels comprising rollers positioned between said outer and intermediate channels for supporting the textile material in its travel, said rollers being arranged relative to said housing and the units which form together therewith said channels so as to be in contact only with the previously dried side of the material.

7. An apparatus according to claim 5, said impeller means and duct means thereof of the units which are in spaced relation to said one wall of said housing being arranged in relation to said means for guiding and passing the textile material so that the drying medium flows countercurrent to the travelling direction of the textile material passing through said outer drying channel constituting said first stage, and said impeller means and duct means thereof of the other ones of said units beingvarranged relative to said means for guiding and passing the textile material so that the drying gas flows in the material travelling direction in the intermediate channel.

8. An apparatus for drying textile thread material with a gaseous medium, comprising a housing structure having planar walls, at least one dryer unit located within said housing structure and disposed in spaced relation to respective planar Walls of said housing structure, said dryer unit comprising a substantially closed casing structure having opposite generally longitudinal, at least partially planar walls, said longitudinal Walls of said dryer unit and said planar Walls of said housing structure forming together a plurality of drying channels for the textile material, means positioned within said housing for guiding and passing the textile material along a predetermined travel path in sequence through said plurality of drying channels and in a predetermined travel direction, impeller means and heater means at least partialy Within said casing structure for circulating and heating said gaseous medium, and duct means interconnecting said impeller means and heater means and connecting same in communication with said drying channels for heating said textile material therein, said drying unit and the longitudinal walls thereof being arranged so as to form a vaporizing section along said travel path of said material between two successive ones of said channels for evaporating oil liquid from the heated textile material, and means Within said housing for maintaining said vaporizing section under a conditioning atmosphere different from that obtaining in said drying channels.

9. Apparatus according to claim 8, said means for maintaining said vaporizing section under a difierent conditioning atmosphere comprising impeller means connected for producing a decreased pressure in said vaporizing section as compared to that obtaining in said drying channels. 5

10. Apparatus according to claim 8, said means for maintaining said vaporizing section under a different conditioning atmosphere comprising heater means connected for producing an increased temperature in said vaporizing section as compared to that obtaining in said drying channels.

11. Apparatus according to claim 8, said means for maintaining said vaporizing section under a different conditioning atmosphere comprising impeller means connected for circulating in said vaporizing section a separate medium over said textile material, said separate medium having a hygroscopic character difierent than that of said gaseous medium in said drying channels.

12. Apparatus according to claim 1, including transverse control flaps pivotally mounted on said units and Within said passageways for control of the direction and quantity of flow of said medium therethrough.

References ited in the file of this patent UNITED STATES PATENTS 1,556,057 Wheller Oct. 6, 1925 2,205,391 Brunkow June 25, 1940 2,456,301 Miller et a1 Dec. 14, 1948 2,462,380 Gauttreau Feb. 22, 1949 2,601,080 Andrews June 17, 1952 2,772,486 Johanson Dec. 4, 1956 2,780,878 Sanborn et al Feb. 12, 1957 v FOREIGN PATENTS v 461,342 Great Britain Feb. 9, 1937 1,037,838 France Sept. 23, 1953 77,450 Netherlands Mar. 15, 1955 

1. A TREATING UNIT FOR ASSEMBLY INTO AN APPARATUS HAVING AT LEAST TWO TREATING CHANNELS FOR TREATING TEXTILE THREAD MATERIAL BY A GASEOUS MEDIUM, SAID UNIT COMPRISING A CLOSED CASING STRUCTURE HAVING OPPOSITE SUBSTANTIALLY PLANAR WALLS, EACH OF SAID OPPOSITE WALLS BEING ADAPTED TO FORM ONE SIDE WALL OF ONE OF SAID TWO TREATING CHANNELS OF SAID APPARATUS, MEANS LOCATED AT OPPOSITE ENDS OF EACH OF SAID WALLS AND FORMING RESPECTIVE GAS INLETS AND GAS OUTLETS AT OPPOSITE ENDS OF EACH OF SAID CHANNELS, SAID GAS OUTLETS BEING MUTUALLY FORMED AT DIAGONALLY OPPOSED CORNERS OF SAID CASING STRUCTURE, IMPELLER MEANS MOUNTED ON AND DEPENDING FROM SAID CASING STRUCTURE FOR CIRCULATING SAID GASEOUS MEDIUM IN A PREDETERMINED DIRECTION, SAID IMPELLER MEANS HAVING AN INTAKE AND AN OUTLET OPENING, AT LEAST ONE OF SAID IMPELLER OPENINGS BEING LOCATED WITHIN SAID CASING STRUCTURE, SAID IMPELLER MEANS BEING LOCATED SO AS TO DRAW SUCTION FROM WITHIN SAID CASING STRUCTURE AND TO DISCHARGE BACK INTO SAID CASING STRUCTURE, DUCT MEANS CONNECTING SAID INTAKE OPENING OF SAID IMPELLER MEANS TO RESPECTIVE ONES OF SAID GAS OUTLETS AND CONNECTING SAID OUTLET OPENING OF SAID IMPELLER MEANS TO RESPEC- 